I'm in the interesting position of having just walked into a situation where the paitent was already dead, and organs had already been harvested from the old company. Rightfully angry customers hadn't had access to the legacy system (it's costs killed the company) in several months.
In the words of Monty Pyhon it was a dead parrot, and I came in to say "It's just resting... It's pining for the Fjords!"
I'm almost a month in on a complete re-architect from scratch. Most customers are overjoyed that the business will be back soon, but I'm afraid their good will is going to be short lived if things aren't running soon.